CVE-2026-16158
criticalpriority · track · 40EPSS 0.004 · 32 %ileEUUSEPSS · scored 2026-10-27
Impact: @fastify/reply-from versions from 8.3.1 up to but not including 12.6.4 build the internal URL cache key by concatenating the destination and source path without a delimiter. Different destination and source pairs can therefore produce the same key while resolving to different upstream URLs. When getUpstream selects an upstream from request data, a URL cached for one upstream can be reused for a request intended for another upstream, causing cross-upstream data access and modification. The default configuration is affected. Setting disableCache to true prevents the behavior. Patches: upgrade to @fastify/reply-from 12.6.4. Workarounds: pass disableCache: true when registering the plugin.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 8.7–10
weaknesses
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affected products (2)
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also known as (2)
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sources
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references (6)
External citations — patches, advisories, analysis.
- https://cna.openjsf.org/security-advisories.htmlcnnvd
- https://github.com/fastify/fastify-reply-from/security/advisories/GHSA-v574-6498-x57vcnnvd
- https://cna.openjsf.org/security-advisories.htmlenisa_euvd
- https://github.com/fastify/fastify-reply-from/security/advisories/GHSA-v574-6498-x57venisa_euvd
- https://cna.openjsf.org/security-advisories.htmlVendor Advisorynvd
- https://github.com/fastify/fastify-reply-from/security/advisories/GHSA-v574-6498-x57vVendor Advisorynvd
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